Landslide at Blubberhouses, North Yorkshire

Blubberhouses locationThe most recent landslides, September 2010, are located to the west of Blubberhouses in North Yorkshire along the A59 road.

Although the landslides did not encroach on the road surface, the A59 was closed between Blubberhouses and Raven’s Peak while remediation work took place.

The BGS Landslide Response Team made a visit to the landslide on 30 September 2010 to investigate the failures. Information was collected for the BGS National Landslide Database and geological maps.

Approximate locations of the landslides. Topography © Crown Copyright. All rights reserved. BGS 10007897/210

 

Remediation work taking place at landslide Blubberhouses 1

 

The completed remediation work at the landslide Blubberhouses 2

News reports

The landslides at Blubberhouses have been reported in the local and national news:

Geology

The underlying bedrock geology of the area is part of the Carboniferous (Namurian) Millstone Grit Group and comprises fine- to very coarse-grained feldspathic sandstones, interbedded with grey siltstones and mudstones, with subordinate marine shaly mudstone, claystone, coals and seatearths. Although no superficial deposits are mapped at this site it is likely that the landslide involved colluvium and weathered bedrock.

The landslides

The Blubberhouses 1 landslide has the characteristics of a flow. A spring 20 metres up the slope is likely to have contributed to the instability at this site. The fence by the side of the road prevented the flow from moving on to the A59 road.

 

Blubberhouses 1, looking downslope, the flow is picked out by tall grass that is common on saturated ground conditions.

 

Blubberhouses 1, looking upslope, water is flowing out of the saturated ground

 

The Blubberhouses 2 landslide was an Earth Slide, the failed material had been removed when the visit took place but the area which had failed was clearly visible. Workers at the site suggested that trees uprooted upslope caused the superficial deposits and bracken that overlay the bedrock to become unstable and slide downslope.

 

Blubberhouses 2, all the slide material has been removed and stone blocks placed at the base to stop any further sliding

 

Thin layer of superficial deposit & bracken overlying the Bedrock

This stretch of the A59 has been prone to landslides in the past; a car was reported to have been covered by earth and rubble by a landslide in 2007.

The Landslide Response Team recorded two remediated landslides west of the two recent slides which are likely to have been the site of this previous incident.

 

Possible site of 2007 slide

 

Another remediated landslide along the A59.

 

Landslide information being recorded using SIGMA·mobile

All the information about the landslide was collected by the Landslide Response Team, using BGS•SIGMAmobile technology.

 

Contact the Landslide Response Team

British Geological Survey
Keyworth
Nottingham
NG12 5GG
E-mail: Landslides team
Telephone: 0115 936 3143
Fax: 0115 936 3276